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From snacktime <snackt...@gmail.com>
Subject Re: eventual consistency and what that means in real world terms
Date Sat, 04 Jul 2009 04:38:49 GMT
On Fri, Jul 3, 2009 at 7:14 PM, Evan Weaver <eweaver@gmail.com> wrote:

> You can (once the API is fixed) make a client request the data from
> every replica on read.  Which ever replica has the most recent value
> will be the value that's returned. That makes sure that reads and
> writes are consistently serialized from the server's perspective, at
> some performance cost.
>
> Weak reads request from one node. Strong reads let you tune the number
> of nodes to check from 1 up to the replica count.
>
> Cassandra, though, is not transactional. You need some kind of lock
> server to guarantee that there aren't read/modify/write races from the
> client's perspective. Zookeeper would probably work.
>

Thanks Evan, that makes sense.

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